wpa_supplicant: Document nl80211 driver in the man page

Signed-off-by: Asbjørn Sloth Tønnesen <hostap@asbjorn.st>

wpa_supplicant/doc/docbook/wpa_supplicant.sgml

@@ -245,10 +245,19 @@
     (<emphasis>wpa_supplicant -h</emphasis>).</para>
 
     <variablelist>
+      <varlistentry>
+	<term>nl80211</term>
+	<listitem>
+	  <para>Uses the modern Linux nl80211/cfg80211 netlink-based
+	  interface (most new drivers).</para>
+	</listitem>
+      </varlistentry>
+
       <varlistentry>
 	<term>wext</term>
 	<listitem>
-	  <para>Linux wireless extensions (generic).</para>
+	  <para>Uses the legacy Linux wireless extensions ioctl-based
+	  interface (older hardware/drivers).</para>
 	</listitem>
       </varlistentry>
 
@@ -538,10 +547,14 @@ wpa_supplicant \
 
     <itemizedlist>
       <listitem>
-	<para>Linux kernel 2.4.x or 2.6.x with Linux Wireless
+	<para>Linux kernel 2.6.30 or higher with
-	Extensions v15 or newer</para>
+	nl80211/cfg80211 support</para>
       </listitem>
 
+      <listitem>
+	<para>Linux kernel 2.4.x or higher with Linux Wireless
+	Extensions v15 or newer</para>
+      </listitem>
 
       <listitem>
 	<para>FreeBSD 6-CURRENT</para>
@@ -557,6 +570,13 @@ wpa_supplicant \
   <refsect1>
     <title>Supported Drivers</title>
     <variablelist>
+      <varlistentry>
+	<term>Linux nl80211/cfg80211</term>
+	<listitem>
+	  <para>This is the preferred driver for Linux.</para>
+	</listitem>
+      </varlistentry>
+
       <varlistentry>
 	<term>Linux wireless extensions</term>
 	<listitem>